error-line-numbers-incorrect-with-multi-line-strings.jsonc

{
    "$schema": "https://schema.management.azure.com/schemas/2015-01-01/deploymentTemplate.json#",
    "contentVersion": "1.0.0.0",
    "variables": {
        "var1": "This
        is
        a
        very
        long
        multi-line
        string
        don't
        you
        know
        and
        I
        can
        keep
        going"
    },
    "functions": [
        {
            "namespace": "udf",
            "members": {
                "a": {
                    "output": {
                        "value": "[variables('var1')]",
                        "type": "int"
                    }
                }
            }
        }
    ],
    "resources": []
}

// Deployment gives: 
// New-AzResourceGroupDeployment : 3:35:33 PM - Error: Code=InvalidTemplate; Message=Deployment template validation failed: 'The template function 'a' at line '14' and column '25' is not valid. These function calls are not  
// supported in a function definition: 'variables'. Please see https://aka.ms/arm-template/#functions for usage details.'.